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Question
The cylinder of radius 12 cm have filled the 20 cm with water. One piece of iron drop in the stands of water goes up 6.75 cm. Find the radius of sphere piece.
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Solution
Radius of cylinder = 12 cm
Height of cylinder = 6.75 cm
Volume of water = πr2h = π x 12 x 12 x 6.75 cm3
Let the radius of iron sphere piece = R cm.
∵ Volume of sphere = volume of water
`4/3` πR3 = π x 12 x 12 x 6.75
R3 = `(π xx 12 xx 12 xx 6.75 xx 3)/(4π)`
R3 = 729
R = `root(3)(729)` = 9 cm.
Hence radius of sphere piece = 9 cm.
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